This invention relates to a latch for positioning and releasably retaining articulated linkages such as the section angles in a combination sofa-sleeper having a foldable bed frame adapted to be collapsed and hidden in the bottom of a sofa when the unit is used for sitting and, more particularly, to a latch for positioning and releasably retaining the head section of the sofa-sleeper in a raised TV position.
Foldable sofa sleepers having pivotally interconnected head, body, intermediate, and foot sections movable between a fully folded or retracted position within the sofa frame and an extended position wherein the sections extend out and over the front rail of the sofa frame are known to the art. In such foldable sofa sleepers, in the extended position, the head, body, intermediate, and foot sections lie substantially coplanar one to the other providing a horizontal surface upon which a mattress is placed to provide a bed. It is further known in the art to provide such foldable sofa sleepers with means to independently tilt or otherwise adjust the head section to an inclined position without moving the body, intermediate, or foot sections to raise the head and shoulders of the user as is often desired for reading, viewing television, and the like. This position of the head section is sometimes referred to in the art as the "TV" position. In prior sofa-sleepers, the adjustable head section has been raised into the inclined position and supported, for example, by a manually releasable member such as a rotatable butterfly latch or in a Z-shaped slot. Representative of prior art patents illustrating the various attempts to provide an independently positionable head section are U.S. Pat. Nos. 3,165,757; 3,298,041; 3,395,409; 3,516,096; 3,868,733; 3,984,883; 4,104,745; and 4,253,205. As may be seen with reference to these patents, they require several additional mechanical elements to position and releasably latch the headrest in the TV position.